Ore concentrating machine



July 14, 1936. E. w. VGREENE'ETAL Filed Oct. 51, 1934 ORE (EONCEIQTEUVIING MACHINE INVENTOR zlmir ATTORNEY 1 Patented July 14, 1936 n i UNITED STATES PATENT OFFICE ORE CONCENTRATING MACHINE Ernest W. Greene and Robert M. Wilbur, Plant City, Fla., assignors to Coronet Phosphate Company, New York, N. Y., a corporation of New York Application October 31, 1934, Serial No. 750,787

9 Claims. (Cl. 209-431) Our invention pertains to a machine for ore and arrangement, hereinafter more particularly concentration. Prior to the present invention referred to in connection with the accomp y n the concentration of finely divided ores, by means drawing in whic 1 is an ometric View of of flotation, was mainly accomplished by aeratthe essential parts of the machine, assembled in ing and agitating a chemically treated pulp of their relative positions to each other. For purthe ore under water. Such a process is generally poses of clarity the supporting structure has not referred to in the art as a froth flotation process been included.

and is carried out in a froth flotation machine. Figure 2 is a sectional view of the machine In this well-known type of apparatus it is custaken on line A-A, and tomary to provide mechanical agitation in order Figures 3, 4 and 5 are isometric views of the 10 to maintain the ore in suspension in the flotation individual types of baflles employed in connection vessels. The floatable constituent'of the ore atwith the apparatus. taches itself to the air bubbles and is thus raised Referring to the drawing, a continuous belt to the surface of the water. A stable froth supis indicated at l, which is preferably a type simports the ore on the water surface and permits ilar to the ordinary rubber conveyor belt. The 15 it to be floated off. width and the length of the belt may be suited In accordance with the tea hin of th presen to the tonnage and conditions desired from the invention a thick pulp of chemically treated ore m In general. r r tonnages can be is fed continuously onto a, moving b 11; Water is handled with wider and longer belts. Tonnages supplied to the belt so as to maintain a flow over up to 3 tons per hour of feed have been handled 2 both sides, B m l t drag on the urf e successfully on a belt which was 30 inches wide of the belt to prevent the non-floatable portion and feet long between pulleys- The e t II of the ore from being washed fi th sides, and operates on pulleys indicated in the drawing at serve to plow up or t over the pile of ore on 2. The bearings for the belt pulleys 2, the supthe belt. The plowing action nus obtained conr n structure r t e ar n e drive tinually presents fresh parts of the ore pile to the mechanism for the belt are not Shown. and ay water surface for flotation. The floatable constitbe Similar to those Used in y conveyor b nuent of the ore floats or is washed off the sides Stallation- The belt may be driven t y a of the belt and is caught in suitable launders Speed up t0 about 100 feet D minute, d p d The non-fioatable constituent of theore remains on the tonnage and e c d t s desired. The 30 on the belt and i finally i d fi t end by direction of motion of the belt is indicated by the the m t of th tarrow. The belt is maintained in a flat, level po- Certain advantages of the invention over previsition by l' of longitudinal PP ous practice in the art are due principally to thebers Shown at M m of the drawmgfact that the ore is maintained at, or near, the The belt 15 fed with fall'ly thick p of c emwater surfa e t, all times Aerating and agitateically treated ore fines through a feed chute 3 ing in the sense used in froth flotation machines located at 0116; end of ne- The belt have been eliminated. A froth is not maintained and the material 011 ill are d. m above on the surface of the water. Since the elevation by means of je e tending alon the u der Sur- 40 of the floatable constituent to the water surface ces o the longitudinally located v d pipes 40 does not depend on air bubbles, larger particles indicated in the drawlng at can be floated. Thus the usual grinding and Baffle members are indicated in the drawing at classifying operations are not nicessary. The l5 d the Same dragging on the side surseparating action of the belt apparatus conface of the belt I, being positioned, with respect structed in accordance with the present inventive t0 t e belt, y means of longitudinally te d conception is more efficient than that of the substationary pieces 8, which are provided with holes aeration, froth flotation machine, because the to receive the ends of the bafiles. The individual floatable constituent of the ore is not raised types of baflles herein employed are indicatedin through any appreciable depth of water, and is detail in Figs. 3, 4 and 5 and the arrangement of mechanically moved into the water surface. The he Same in j 1 is preferable When the machine 50 side edges of the belt, off which the concentrates is ope a Wlth belli length of fifty feet.

flow, are as low as, or lower than, the ore on the The battle 5 shown in Figure 3 is constructed belt, by attaching a piece of sheet metal to a small' Our invention further includes other advanbent metal rod. The sheet metal may be any tages and novel features of design, construction metal of moderate thickness and adequate rigid- 55 ity. On a belt thirty inches wide, 20-28 gauge galvanized iron baflles which were 2 /2 x 18 inches have been used, although these specifications are not strictly required. The metal rod is preferably about inch in diameter and may be any desirable material. Rust and corrosion resistant metals are preferable for these baflles. Bafiles 6 and 1, shown in Figures 4 and 5, are bent rods, and the preceding description applies with equal effectiveness to their construction. The angle which the bafiles 5, 6 and I make, with the direction of motion of the belt I, vary considerably, angles of from 20 to 45 having been found to be most efficient in practicaluse. The baflles are angularly positioned with respect to the belt to direct the ore toward the central portion of the same during movement. 'The parallel arrangement of the bafiles, which extends substantially along the entire side of the belt, further provides an unimpeded passageway along the same for the movement of the ore. In the construction illustrated, the baffles extend less than half way across the width of the belt.

The functions of these .bafiles are to turn over the pile of ore as it is moved past them by the belt and to prevent the nOn-floatable constituent being washed off the side edges of the belt. In the former respect their action is .a plowing action which raises the ore above the water surface and then drops it into the water again. The latter effect ispurely a battle action. The baflles 5 in Figure 3 are more effective for keeping the non- I fioatable material on the belt, while the types 6 and 'I have a better turning action on the material. The arrangement of the bailies on the belt will depend on the conditions and the results desired. We' have found that a desirable arrangement for a roughing operation is to equip the first half of the belt with type 5 bailies and the last half with types 6 and I baifles. We have found that a cleaning operation on medium grade concentrates works well with type 5 bafiles on the whole length of the belt.

The spacing of the bafiles along the belt depends on the width of the belt, the speed' of the belt, the tonnage handled, and the grade of product taken off. We have found that a. spacing of about 6 inches produces good results under quite a wide variation of conditions. The transversely level rigid baliles of the invention as illustrated are relatively closely spaced in parallel arrangement to extend substantially along the entire side surfaceof the belt. The position of the baffles along the side of the belt and only partially extending across the width of the same provides an area adjacent the inwardly disposed ends of the bafiles for the free passage of ore along the belt.

The fioatable constituent of the treated ore moves off the sides-of the belt and is caught in a concentrate launder, shown at 9 in the drawing.

off, the pile, this water carries a fioat concentrate on its surface. The plowing action of the battles causes a fioat concentrate to form where the ore is moved out of, or into, the water on the belt. On flowing off of the belt the water washes with it some coagulated material. There is never any appreciable depth of water maintained on the fiat belt. The ore on the belt is thus always at, or near, the water surface.

The belt machine, which has been described above, would undoubtedly lend itself to the concentration of fine metalliferous and nonmetalliferous ores in general. The apparatus has been thoroughly tested on fine Florida phosphate ores. The belt used for this purpose-was 30 inches wide and 50 feet between pulleys.

These tests were run with tailings from a screening concentration of Florida pebble phosphate rock. This material consisted principally of fine bone phosphate of lime and fine silica gangue which had passed a 0.032 inch screen and which had been deslimed. In, all tests the deslimed phosphate fines were mixed with approximately the following amounts of reagents in pounds per ton of dry ore: 1 pound of solid caustic soda; 5 to 6 pounds of crude oil; 1 to 2 pounds of a crude mixture of fatty acids; 0 to 0.7 pounds of pine oil; sufiicient water to give a freely flowing pulp.

The following examples have been taken from over '70 tests-on the apparatus, and include two roughing tests and two cleaning tests. In the roughing tests low grade heads were fed to the apparatus, and medium grade concentrates and clean tailings were produced. In the cleaning tests medium grade material, which had been obtained as roughing concentrates, was fed to the apparatus without any further addition of reagents. These cleaning tests produced high grade concentrates and a middling.

Example 1-(Roughing test).-The first half of the belt was equipped with type 5 bailles and the last half with type '7 baffles. The linear speed of the belt was 38 feet per minute. A total of 600 pounds ofchemically treatedore fines was fed to the watered belt ata rate of 15 long tons per hour. The results are recorded in the following Weights B. P. L. Recoveries Percent Percent Percent 100.0 37. 36 100.0 52. 6 66. 03.9 Tar 47.4 4.80 6.1

recorded in the following table.

Weights B. P. L. Recoveries Percent Percent Percent Example 3--(Cleaning test) .-The first half of the belt was equipped with type 5 baflles and the last half with types 6 and 7. The linear speed of the belt was 38 feet per minute. Water was supplied to the belt at-the rate of 217 gallons per minute. Approximately 1200 pounds of roughing concentrates were fed to the belt at a rate of 15 long tons per hour. The results are recorded in thefollowing table.

Weights B, P. L. Recoveries- Percent Percent Percent Heads 100. 60. 64 100. 0 001108 70. 6 74. 88 87. 2' Middl ..i 29. 4 26. 38 12. 8

Example 4'-(Cleam'ng test) .The whole length of the belt was equipped, with type 5 baffles., The linear speed of the belt was 72' feet per minute. Water was supplied to the belt at the rate of 285 gallons per minute. Approximately 1200 pounds of roughing concentrates were fed to the belt at a rate of approximately 30 tons per hour. The results are recorded in the following table.

Weights P. L. Recoveries Percent Percent Percent While wehave shown and described the pre-. ferred embodiment of our invention, we do notdesire to limit ourselves to the specific form illustrated, but may alter the construction and arrangement of parts'as occasion requires without enlarging the scope of our invention or depart ing from the spirit thereof as contained in theappended claims. i We claim as our invention:

' 1. An ore concentrating machine comprising a belt apparatus having an ore receiving uppersur- 2. An ore concentratingmachi ne comprising a belt apparatus having a flat horizontal ore re- 0 ceiving' upper belt surface, means for driving said belt apparatus, a plurality of stationary laterally -located baffles in contact with the upper belt surface, said baflles substantially extending the length of the upper belt surface along its'respec- 5 tive side portions and being situated at an inclination of from 20 to 45 with respect to a center line indicating the direction of motion of the belt, and means for supplying 'ore and fluid to the belt.

' .3. An ore concentrating machine comprising .a

) belt apparatus having a flat horizontal ore receiv-" ing upper belt surface, -means for driving said belt apparatusya'plurality of fixed bafiles extending substantially throughout the length of the movable upper belt surface and along the respective sides of the same, said bafiies being angularly situated at an inclination of from 20 to 45 with respect to a center line indicating the direction of motion of the belt, the portion of the apparatus between the respective side baflies being open to 1 permit the direct passage of ore along the belt, and means for supplying ore and fluid to the belt. 4. An oreconcentrating machine comprising a -'of 'motion of the belt, said apparatus-providing a means for driving the belt apparatus, and means for supplying ore and fluid to the free passage belt apparatus having a flat horizontal ore receiving upper belt surface, means for driving said' belt apparatus, a plurality of stationary baflles injcontact with the movable upper belt surface and substantially extending throughout the, length 5 of the beltin rows along the respective side surfaces of the same, the baffles being angularly situated at an inclination of from20 to 45? with respect to thecenter line indicating the direction 10 direct passageway along the belt between the baffles for the ore, and means for supplying ore andfluid to the belt.

-5; An ore'concentrating machine comprising a 1 belt apparatus having a flat ore receiving upper belt surface, means for driving-said belt apparatus, a plurality of fixed perpendicular plate and horizontal rod babies in contact with'the movable upperv belt surface, said baffles extending in rows along the respective sides of the upper belt surface and being angularly positioned to direct tlie ore toward the longitudinal center of the belt during its movement and means for supplying ore. and fluid to the belt.

v6. An ore. concentrating machine comprising a ing said belt apparatus, and means for supplying ore and fluid to the same.

7 An ore concentrating machine comprising a belt apparatus having a flat ore receiving upper surface, means for driving said belt apparatus,

a plurality of fixed baflles situated above'the movable ore receiving surface,- said' baffles being arranged 'in rows along the respective sides 'of the belt surface todirect the ore moving upon the same toward its longitudinal center, and means. for supplying ore and fluid to the apparatus.

8. In an ore concentrating machine, the combination of a belt apparatus having a transversely level ore. receiving upper surface, a plurality of relatively closely spaced rigid baflles situated above the ore receiving surface of the belt, said bafiles being located in parallel arrangement along substantially the entire side of the belt surface and being'angularly positioned to point in direction of motion of the belt, the baflies extending o partially across the-width of the belt to provide an area adjacent the-inwardly disposed ends of the same for the free passage of ore upon the belt,

. area of the belt.

9. In an ore concentrating machine, the-cornbination of a belt apparatus'having a substantially flat ore receiving upper surface, a lurality oi" relatively closely'spaced, angularly l bafiles situated in a'fixed positionwith relation to the upper surface of the belt, said baffies being located in Substantially Parallel arrangement along the entire side of the belt surface, the baflies extending partially across the width of .the belt 5' d to provide an area'ad'jacent the inwardly disposed ends of the samefor-the 'freepassage of ore upon the belt, means for driving said belt apparatus, and means for supplying ore and fluid to the free passage area .of the belt.

70 .ERNEST- W. GREENE.

R. M. WILBUR.

ated, rigid 

